Statcom and load tap changing transformer (LTC) in Newton Raphson Power Flow: Bus voltage constraint and losses

In recent years, the underlying algorithm used for solving power flow problems is the Newton Raphson method (Peterson et al., 1971). In this paper the direct inclusion of STATCOM and load-tap-changing transformer (LTC) models into Newton- Raphson power flow algorithms is studied. The models are developed from the first principle. The performance of the STATCOM and the load-tap-changing transformer (LTC) into the power flow using the Newton Raphson method is tested for reliability towards the convergence, accuracy and voltage constraint of bus voltage and losses on the IEEE 4 bus test system. The results show that the proposed method with STATCOM possesses excellent convergence characteristics. Furthermore the system losses are less compared with the LTC for the same voltage constraint at a bus where the STATCOM and the LTC are connected. The proposed STATCOM model can be easily extended to any FACTS device with minor modification in the Jacobian matrix of the power flow algorithm.